Effects of sterilization and storage on the properties of ALP-grafted biomaterials for prosthetic and bone tissue engineering applications

Abstract

Grafting of the biomaterial surfaces with biomolecules is nowadays a challenging research field for prosthetic and bone tissue engineering applications. On the other hand, very few research works investigate the effect of the sterilization processes on the properties of functionalized biomaterials. In this study, the effects of different sterilization techniques (e.g. gamma and electron beam irradiation, ethylene oxide) on the enzymatic activity of bioactive glasses and Ti6Al4V grafted with alkaline phosphatase (ALP) have been analyzed. Sterility maintenance and in vitro bioactivity of the sterilized surfaces have also been investigated. Finally the effect of packaging and storage conditions has been considered.

Titanium implants coated with UV‐irradiated vitamin D precursor and vitamin E: in vivo performance and coating stability

“…Biological molecules usually present low stability under environmental conditions as they tend to denature in activity due to humidity and heat (Ferraris et al. ). Indeed, several investigations confirm the effect of storage temperatures on the stability of different drugs (Tian et al.…”

“…Thus, orthopedic and dental implants are sold as storable medical devices, but the aging effects on them have barely been addressed ). Although Ti is the most commonly used material for bone implants due to its outstanding properties (Palmquist et al 2010), the addition of bioactive molecules to the implant surface makes them more difficult to handle and store than unmodified ones, which could limit their clinical use (Ferraris et al 2012). Therefore, developing a bioactive coating with good stability and able to maintain its bioactivity during storage is of high interest for future clinical use.…”

“…), the addition of bioactive molecules to the implant surface makes them more difficult to handle and store than unmodified ones, which could limit their clinical use (Ferraris et al. ). Therefore, developing a bioactive coating with good stability and able to maintain its bioactivity during storage is of high interest for future clinical use.…”

Matrix‐Bound Presentation of Bone Morphogenetic Protein 2 by Multilayer Films: Fundamental Studies and Applicationsto Orthopedics

“…The presence of biologically active molecules makes these devices more difficult to handle, store, and sterilize than traditional biomaterials. Such difficulties can hamper the clinical diffusion of these innovative solutions, limiting them to the research level [87]. Developing a device coated with BMP-2 that has shelf-life stability and sterilization resistance is of high clinical interest.…”

“…In contrast, γ-irradiation is the appropriate sterilization method for heat-sensitive materials [88] because the temperature does not noticeably increase during or after the process [89]. For instance, conventional 25-kGy γ-sterilization procedure can be applied to ALP enzyme-grafted biomaterials without noticeable loss of ALP activity [87]. Several other literature reports suggested that γ-irradiation is less detrimental for growth factor stability and, therefore, this method has already been applied to BMP-2 using an irradiation dose of 25 kGy [90][91][92][93].…”